海蛞蝓，或许很多人对这名字并没有很陌生，其颜色五彩斑斓，形态多样，一直深受很多潜水爱好者的喜爱。但是它还有另外一个身份：是世界上发现的第一种可合成植物色素叶绿素的动物。这似乎像角色扮演里错拿植物剧本的伪装者，那它究竟是一种怎样新奇的存在，我们一起来了解一下吧。

The sea slug, a name perhaps familiar to many people, has been loved by many divers for its beautiful colors and diverse forms. But it has another identity that it is the first animal found in the world that can synthesize the chlorophyll. It seems that the sea slug is a kind of disguised animal. Therefore, what kind of novelty it has? let’s learn more about it.

海蛞蝓，因其头上有两对触角突出如兔耳，而又名海兔，还有称海麒麟、海燕等。但是它们既不与兔同属也不与蛞蝓同科，更不属海燕，而是属于软体动物门>海生腹足纲>后塞目>裸腮亚目>海神腮科>海神腮属。目前已知有4700多种。

The sea slug is also known as sea rabbit because it has two pairs of tentacles protruding from its head like rabbit ears, and it is also called sea unicorn and sea swallow. However, it is not in the same genus as rabbit, slug and sea swallow, and it belongs to the Phylum Mollusca>Mollusca Gastropoda> Nudibranchia> Glaucus Gill Family> Glaucus Gill Genus. There are more than 4,700 species known until now.

分布范围：

Distribution:

海蛞蝓分布于世界各地海域，包括热带和南极洲海域，主要广泛分布于较暖的海区。

The sea slugs can be found in waters around the whole world, including tropical and Antarctic waters, and they are mainly in warmer marine areas.

个体特征：

Individual Characteristics:

海蛞蝓种类繁多，形态各异，运动时身体可变形。大部分体型较小，不超过十厘米。头顶有两只似兔耳的触角，能感知海水温度、深度等。体外物皮毛，壳退化，只有一层薄而半透明的角质膜覆盖着身体。身体色彩鲜艳，根据所食对象和所处环境不同会有各种不同颜色。

The sea slugs are morphologically diverse, and their bodies can be deformed during movement. Most of them are small with no more than 10 cm in size. The top of their head exists two tentacles like rabbit ears, which can sense the temperature and depth of seawater. There is only a thin and translucent keratinous membrane covering the body. Their bodies are brightly colored and will have a variety of different colors depending on the objects they eat and the environments they are in.

学名Janolus Fuscus（罗马神话中的双头神）（图片来源于百度）

食物：

Foods:

以藻类、水母、海葵、海绵、水螅等生物为主。4.繁殖方式： 海蛞蝓属于雌雄同体动物，异体交配。当一只海蛞蝓的雄性器官与另一只海蛞蝓的雌性器官交配间隔一段时间后，可交换性器官进行再次交配。

The sea slugs feed on algae, jellyfish, anemones, sponges, hydroids, etc. Reproduction: Sea slugs are hermaphrodites and depend on allogamy. When the male organ of a sea slug is mated with the female organ of another sea slug after a period of time, the sexual organs can be exchanged for mating again.

制敌妙招：

Fighting against the Enemy:

如此招人喜爱的海蛞蝓究竟怎样抵御敌人呢？由于缺少贝壳的保护，海蛞蝓进化出了几种机智的抵御机制。一些种类可以合成有毒化合物，比如硫酸；一些种类可以利用有毒食物中的有毒化合物抵御敌人；还有一些食用含刺细胞的生物（水母、水螅、海葵等）转化利用被捕食者的刺细胞进行防御。

How can such popular sea slugs defend themselves against enemies? Lacking the protection of shells, sea slugs have evolved several defense mechanisms. Some species can synthesize toxic compounds, such as sulfuric acid; some species can use toxic compounds in toxic food to defend themselves against enemies; and some eat organisms that contain stinging cells (jellyfish, hydroids, anemones, etc.) and then transform the stinging cells for defense.

特殊海蛞蝓： 藻类海蛞蝓（非正式定名），因其长相似小绵羊所以又称叶羊，一开始因食用海藻其身体呈绿色，是世界上极为罕见的能进行光合作用的动物。他们能将所食海藻中的叶绿体整合到自己的皮肤中进行光合作用，但是并非捕食一次就能满足一生所用，因为海蛞蝓不能自身合成光合作用所需的全部蛋白质，所以它仍然需要不断补足海藻。

Special sea slugs. Algae sea slugs (informal name), also known as leaf sheep because of their resemblance to small sheep, are extremely rare animals in the world that can photosynthesize, as their bodies are green due to the algae they eat. They can integrate chloroplasts from the algae they eat into their own skin for photosynthesis, but the chloroplasts gained from one predation do not satisfy their lifetime use because they cannot synthesize all the proteins needed for photosynthesis by themselves and still needs to replenish the algae continuously.

叶羊（图片来源于百度）

另一种能进行光合作用的动物——绿叶海蛞蝓似乎更高级，因为它能直接窃取合成叶绿素所必需的基因，也能提供光合作用所需蛋白质，已有研究结果发现，绿叶海蛞蝓仅靠幼年吃的藻类就能存活九到十个月，而绿叶海蛞蝓的寿命大部分不超过一年。绿叶海蛞蝓还能将这种遗传物质，遗传给下一代，这些后代可以合成自己的叶绿素。但其后代在吃掉足够的藻类以获取必要的叶绿体之前他们仍然不能进行光合作用。

Another animal that can photosynthesize, the green leaf sea slug, seems to be more advanced because it can directly get the genes necessary to synthesize chlorophyll and also provide the proteins needed for photosynthesis. The results from past studies show that green leaf sea slugs can live for nine to ten months just depending on the algae that they eat when they are young even though most green leaf sea slugs do not live more than one year. The green leaf sea slugs can also pass on this genetic material to the next generation which can synthesize their own chlorophyll. However, the offspring are still unable to photosynthesize until they have eaten enough algae to obtain the necessary chloroplasts.

绿叶海蛞蝓（图片来源于百度）

虽然不能完全脱离植物自主进行光合作用，但无论怎样它们都已经打破了人们的局限认知，给予我们对自然界新的思考。

Although they cannot fully photosynthesize without plants, they have in any case broken our limited perceptions and given us a new way of thinking about the natural world.

参考资料：

[1]海蛞蝓可生成叶绿素似为动植物混合体(图)．新浪科技 [引用日期2016-09-07]

[2]庞世烨，庞世瑜，周浩平等.中国少儿百科全书海洋生物.天津：天津教育出版社.2021[3]溥奎等.动物地理上.长春:吉林美术出版社.2007

[4][美]梅拉尼· L. J. 斯蒂斯尼著，祝茜等译.伟大的海洋.重庆：重庆大学出版社.2017

简述翻译者：海南大学研究生 谭佐莉